They were following a call by the Third Way, a far-right party with suspected links to neo-Nazi groups, for its members to stop illegal crossings near the town of Guben on the German-Polish border.
A spokesman said police confiscated the weapons of 50 suspects and escorted them out of the Guben area late Saturday and early Sunday. Some of the suspects had traveled to the Polish border from other parts of Germany.
Dozens of people held a vigil in Guben on Saturday to protest a planned far-right patrol.
Germany has deployed an additional 800 police officers to the Polish border to control the flow of migrants trying to enter the EU from Belarus, the interior minister was quoted as saying on Sunday.
“At present there are hundreds of officers on duty there day and night. If necessary, I am ready to strengthen them even more,” Horst Seehofer told Bild am Sonntag newspaper.
Seehofer said there have already been 6,162 unauthorized entries from Belarus and Poland to Germany this year.
Last week, Seehofer said Germany did not intend to close the border with Poland, but on Sunday he said the country may have to consider resuming control.
“If the situation on the German-Polish border does not ease, we will also have to consider whether this step should be taken in coordination with Poland and the State of Brandenburg. The decision will come to the next government,” he said.
Three German parties working to form a coalition government say they aim to end talks by the end of November and elect Social Democrat Olaf Scholz as chancellor in December.
Several EU states accused Minsk of sending illegal migrants across the border into the EU, which pressured Belarus to impose sanctions after the controversial re-election of President Alexander Lukashenko in August 2020.
Lukashenko denies this and blames the West for what he says was a humanitarian disaster this winter, when migrants were left stranded at the Belarusian-Polish border.
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